You are right about the "Innocent until proven guilty".
Unfortunately with Paul's past it's very difficult to believe in his innocence when he has done so many bad things. And as Daniel said about Paul that he has the 2 sides to him. Daniel said that he believes that Paul didn't mean to hurt anyone.
But you can admit that it was strange coincidence when just before the explosion Paul asked Terese and Daniel to leave Lassiteres and go to Robinson's. If we (the viewers) didn't know that Paul hasn't caused the explosion then it would be difficult for us to think he is innocent.
Another coincidence was with his briefcase, when he asked Steph not to let anyone to enter the Robinson's without a warrant and then Steph finds the boilers blueprints in it.